"Uwe" wrote in message
...

I monitor the output signal on my scope and notice that right after key
down
the waveform contract just a bit and the tone changes pitch. I guess this
is
called chirp. I normally use B+ 200V.
If I increase the voltage lets say to 300V this effect becomes much more
pronounced.
I still use an external bench supply capable of much higher currents and
I
don't think it is a power supply weakness. In fact putting a VOM on the
supply line shows no sag in my supply voltage.

I think 200 V is enough. Someone here probably knows what the AC-1 design
voltage was, but I'm sure it wasn't 300 V, and may be have more like 150 V.
While the 6V6 can handle higher voltages, as a keyed crystal oscillator, you
don't want to overdo it. You could fracture a crystal, too.

There's quite a bit of AC-1 lore online. Use
http://www.google.com/search?q=ameco+ac-1 to find it. I even found a copy of
the original AC-1 manual, but it doesn't show circuit voltages.

Congrats on getting your ticket and making your first QSO. Now it's time to
put this antique away and build some safe, cool, solid-state gear!

73,

"PM"